Organosilicon chemistry. Part XVIII. Some reactions of 1,3-dimethyl-1,3-diphenyl-, 1,1,3,3-tetraphenyl-, and 1,1-dimethyl-3,3-diphenyl-1,3-disilacyclobutane
Abstract
Ring-opening of 1,3-dimethyl-1,3-diphenyl- and 1,1,3,3-tetraphenyl-1,3-disilacyclobutane takes place on treatment with halogens, hydrogen halides, lithium aluminium hydride, sodium hydroxide, or sulphuric acid, but the reactions with halogens and hydrogen halides are complicated by silicon-phenyl bond scission. 1,1 -Dimethyl-3,3-diphenyl-1,3-disilacyclobutane is conveniently prepared by reaction of an equimolar mixture of the silanes Me2SiCl·CH2Cl and Ph2SiCl·CH2Cl in tetrahydrofuran with magnesium. It reacts with hydroxide, methoxide, ethoxide, hydride ion, hydrogen chloride, or hydrogen bromide to give major products arising via SiMe2–CH2 bond scission, but in contrast it reacts with chlorine or bromine to give major products arising via SiPh2–CH2 bond scission.